It had no name. Just a string of code: [MISSINGNO._ACT_04]
Inside that folder, one file: Luca.dat.
Luca tried to run. The game didn't let him. The silhouette lunged, and the screen fractured into a cascade of corrupted polygons. His Switch vibrated violently, then went black. Pokemon Diamante Brillante -NSP- -Actualizacion...